Errormessage Could Not Be Sent. Mailer Error: Smtp Connect() Failed

We get the following message when we change an order status.

ErrorMessage could not be sent.
Mailer Error: SMTP connect() failed.
https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
Customer gets the order change email, we don't.
We didn't do any upgrade or changed something on the server.
What can be wrong?

We get the following message when we change an order status.

ErrorMessage could not be sent.
Mailer Error: SMTP connect() failed.
Customer gets the order change email, we don't.
We didn't do any upgrade or changed something on the server.
What can be wrong?

Hi!

Please, make sure that SMTP server settings are set up correctly at the Settings: E-mails page of your admin panel. You can contact your mail server administrator for the correct settings.

Hi!

Please, make sure that SMTP server settings are set up correctly at the Settings: E-mails page of your admin panel. You can contact your mail server administrator for the correct settings.

Hi, we unchecked: Use SMTP authentication:

Now we get the following message:

ErrorMessage could not be sent.
Mailer Error: SMTP Error: The following recipients failed: customer@hereaddress.com: Relaying not allowed
×ErrorMessage could not be sent.
Mailer Error: SMTP Error: data not accepted.SMTP server error: DATA command failed Detail:
Your email appears to be unsolicited and was not accepted by LOCALDOMAIN .
Please try using an alternative email or if you want your email accepted resend it with the code aArcI66LeQ appended to your email subject, thank you.
SMTP code: 554 Additional SMTP info: 5.7.1

Hi, we unchecked: Use SMTP authentication:

Now we get the following message:

ErrorMessage could not be sent.
Mailer Error: SMTP Error: The following recipients failed: customer@hereaddress.com: Relaying not allowed
×ErrorMessage could not be sent.
Mailer Error: SMTP Error: data not accepted.SMTP server error: DATA command failed Detail:
Your email appears to be unsolicited and was not accepted by LOCALDOMAIN .
Please try using an alternative email or if you want your email accepted resend it with the code aArcI66LeQ appended to your email subject, thank you.
SMTP code: 554 Additional SMTP info: 5.7.1

It seems like your SMTP mail server does not accept sending of emails from the email address that is specified at the Settings > Company page of your admin panel. In order to resolve this issue, please contact your mail server administrator for the correct SMTP settings.

It seems like your SMTP mail server does not accept sending of emails from the email address that is specified at the Settings > Company page of your admin panel. In order to resolve this issue, please contact your mail server administrator for the correct SMTP settings.

Hosting provider moved our website to another server, problem solved.

Hosting provider moved our website to another server, problem solved.

It's good to know! Thanks for sharing information on how the issue has been solved.